**Author details**

186 Recent Advances in Crystallography

**6. Electrochemical selectivity** 

detect the amount of enantiomeric excess in the mixture.

grown from a racemic tartaric acid, no selectivity was observed.

**(A) (B)** 

An interesting aspect of the electrodeposited chiral films is that they show chiral selectivity. [18, 19] In this process, the chiral film selectively oxidizes the chiral molecules in the solution. This property of the chiral films can be utilized post enantiomeric separation to

Researchers have studied the electrochemical oxidation of sugars on chiral Pt surfaces. [15] In this study, enantiospecific electrochemical oxidation of glucose was demonstrated on Pt(643) and Pt(-6-4-3) surfaces. Recent studies show that chiral cyclodextrin based coatings applied to a three-transducer microsystem shows distinct chiral discrimination for different compounds. [68] CuO has been shown to be catalytic for the electrochemical oxidation of amino acids, carbohydrates and amines with very high sensitivities. [69-71] It has been reported that increased sensitivity for the electroxidation of amino acids with an increase in solution pH. [72] Electrodeposited chiral CuO films also show chiral selectivity in high pH chiral solutions. [18] It was shown that the film grown from L-tartaric acid selectively oxidizes L-tartaric acid over D-tartaric acid, whereas the films grown from D-tartaric acid does the opposite. For the films

**Figure 10.** Cyclic voltammograms in unstirred solutions of alkaline solutions of L-, D-, and DL- tartaric acid by scanning from open circuit potentials to 0.75 V vs. SCE at a scan rate of 10 mV/sec for the films

grown (A) L-malic acid, (B) D-malic and (C) DL-malic acid

**(C)** 

Rakesh Gudavarthy *Missouri University of Science and Technology, Rolla, Missouri, USA Current address: Intel Corporation, Hillsboro, OR, USA* 

Elizabeth A. Kulp *Missouri University of Science and Technology, Rolla, MO, USA* 
